1. Field of the Invention
The invention is an implement and a method for colorimetrically determining whether a woman is fertile or pregnant.
2. Description of the Prior Art
There is considerable interest in detecting the fertile period of women and also considerable interest in ascertaining whether a woman is pregnant in the early stages of gestation. This interest in detecting the fertile period is important to those women who desire to have an offspring, and also to those who wish to avoid having an offspring. The interest in detecting the presence of pregnancy is important to those who desire to provide medical care for the health of the female and the offspring and also for interrupting an unwanted pregnancy.
Test implements and methods for colorimetrically determining whether a woman is fertile are described in U.S. Pat. Nos. 3,406,016 and 3,699,005. Both patents describe test implements in the form of a strip of paper. In U.S. Pat. No. 3,406,016 the paper strip is impregnated with a peroxidase and guaiac. The strip changes color when wet with saliva if the woman is in her fertile period, the change being caused by the presence of peroxide in the saliva. In U.S. Pat. No. 3,699,005 the paper strip is impregnated with indoxyl phosphate or 5-bromoindoxyl phosphate and a nontoxic buffer that maintains a pH of 10.0-10.3. The strip changes color when wet with saliva if the woman is in her fertile period, with the color change being caused by increased levels of alkaline phosphatase in the saliva during the fertile period. Colorimetric assays for measuring acid phosphatases in biological liquids are known from U.S. Pat. No. 3,595,756.